Ground moisture rise vs foundation crack entry
A broad low band differs from a defined crack pathway.
Low foundation walls, slab edges and ground-connected materials
Foundation walls and wall-floor junctions
Wet seasons, saturated soil or persistent ground moisture
Rain, thaw or saturated soil
Low damp band, salts and coating failure
Water, staining or salts following a visible crack
Map moisture height and inspect exterior drainage and ground cover
Document entry during weather and inspect exterior drainage
Only one high localized spot
No crack or weather relationship
Do not repair the resemblance. Verify the pathway.
Color and shape can overlap. Timing, location and a repeatable check usually carry more diagnostic weight.